After completion of routine invasive coronary angiography and upon determining that the patient has either (1) an epicardial de novo coronary artery lesion of indeterminate severity (>50% to <70% stenosis) that requires IVUS analysis for further delineation of stenosis (blockage) severity; or (2) a severe epicardial de novo coronary artery lesion that requires PCI for definitive treatment, combined NIR-IVUS imaging will be carried out in the target-vessel. Upon completion of NIRS-IVUS imaging of the target-vessel, percutaneous intervention will be performed in the standard fashion if deemed clinically appropriate. Upon completion of target-vessel intervention, NIRS-IVUS imaging will then be repeated in the target-vessel.